{{Note|{{ic|glxgears}} is not a benchmark tool for performance comparison between multiple systems.}}

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User trying {{ic|glxgears}} to check system graphics performance, may notice it showing results around 60 FPS. For example:

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[...]

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311 frames in 5.0 seconds = 61.973 FPS

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311 frames in 5.0 seconds = 62.064 FPS

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311 frames in 5.0 seconds = 62.026 FPS

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[...]

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That is not caused by performance regression, but because the system graphics are using [[Wikipedia:Analog television#Vertical synchronization|vertical synchronization]], which is the display's native frames per second.

Hardware accelerated video decoding/encoding on newer GPUs is possible through the VA-API driver provided by libva-intel-driver package also, available in the official repositories.

Note: User may need to install lib32-intel-dri in 64-bit systems to use 3D acceleration in 32-bit programs.

Configuration

There is no need for any kind of configuration to get the X.Org running (an xorg.conf is unneeded, but needs to be configured correctly if present).

For the list of options, type man intel.

KMS (Kernel Mode Setting)

KMS is required in order to run X and a desktop environment such as GNOME, KDE, Xfce, LXDE, etc. KMS is supported by Intel chipsets that use the i915 DRM driver and is enabled by default as of kernel v2.6.32. Versions 2.10 and newer of the xf86-video-intel driver no longer support UMS (except for the very old 810 chipset family), making the use of KMS mandatory[1]. KMS is typically initialized after the kernel is bootstrapped. It is possible, however, to enable KMS during bootstrap itself, allowing the entire boot process to run at the native resolution.

Note: Users must remove any deprecated references to vga or nomodeset from boot configuration.

To proceed, add the i915 module to the MODULES line in /etc/mkinitcpio.conf:

MODULES="i915"

Now, regenerate the initramfs:

# mkinitcpio -p linux

and reboot the system. Everything should work now.

Module-based Powersaving Options

The i915 kernel module allows for configuration via /etc/modprobe.d/i915.conf wherein users can define powersavings options. A listing of options is available via the following command:

$ modinfo i915 | grep power

An example /etc/modprobe.d/i915.conf:

options i915 i915_enable_rc6=7 i915_enable_fbc=1 lvds_downclock=1

Tips and tricks

Choose acceleration method

UXA - (Unified Acceleration Architecture) is the mature backend that was introduced to support the GEM driver model.

SNA - (Sandybridge's New Acceleration) is the faster successor for hardware supporting it.

The default method is UXA, which is more stable but slower than SNA. SNA has improved performance, but still considered experimental. Check benchmarks done by Phoronix [2]. These can be found here for Sandy Bridge and here for Ivy Bridge. UXA is still a solid option, if experiencing trouble with SNA.

To the new SNA method, create /etc/X11/xorg.conf.d/20-intel.conf with the following content:

Setting scaling mode

center: resolution will be kept exactly as defined, no scaling will be made,

full: scale the resolution so it uses the entire screen or

full_aspect: scale the resolution to the maximum possible but keep the aspect ratio.

If it does not work, try:

$ xrandr --output LVDS1 --set "scaling mode" param

where param is one of "Full", "Center" or "Full aspect".

KMS Issue: console is limited to small area

One of the low-resolution video ports may be enabled on boot which is causing the terminal to utilize a small area of the screen. To fix, explicitly disable the port with an i915 module setting with video=SVIDEO-1:d in the kernel command line parameter in the bootloader. See Kernel parameters for more info.

If that does not work, try disabling TV1 or VGA1 instead of SVIDEO-1.

H.264 decoding on GMA 4500

The libva-driver-intel package provides MPEG-2 decoding only for GMA 4500 series GPUs. The H.264 decoding support is maintained in a separated g45-h264 branch, which can be used by installing libva-driver-intel-g45-h264AUR package, available in the Arch User Repository. Note however that this support is experimental and not currently in active development. Using the VA-API with this driver on a GMA 4500 series GPU will offload the CPU but may not result in as smooth a playback as non-accelerated playback. Tests using mplayer showed that using vaapi to play back an H.264 encoded 1080p video halved the CPU load (compared to the XV overlay) but resulted in very choppy playback, while 720p worked reasonably well [3]. This is echoed by other experiences [4].

Setting gamma and brightness

Intel offers no way to adjust these at the driver level. Luckily these can be set with xgamma and xrandr.

Gamma can be set with:

$ xgamma -gamma 1.0

or:

$ xrandr --output VGA1 --gamma 1.0:1.0:1.0

Brightness can be set with:

$ xrandr --output VGA1 --brightness 1.0

Troubleshooting

Blank screen during boot, when "Loading modules"

If using "late start" KMS and the screen goes blank when "Loading modules", it may help to add i915 and intel_agp to the initramfs. See the above KMS section.